5655821 has 4 divisors (see below), whose sum is σ = 5733372. Its totient is φ = 5578272.

The previous prime is 5655791. The next prime is 5655823. The reversal of 5655821 is 1285565.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4182025 + 1473796 = 2045^2 + 1214^2 .

It is a cyclic number.

It is not a de Polignac number, because 5655821 - 2⁶ = 5655757 is a prime.

It is a super-2 number, since 2×5655821² = 63976622368082, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5655823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38666 + ... + 38811.

It is an arithmetic number, because the mean of its divisors is an integer number (1433343).

Almost surely, 2^5655821 is an apocalyptic number.

It is an amenable number.

5655821 is a deficient number, since it is larger than the sum of its proper divisors (77551).

5655821 is an equidigital number, since it uses as much as digits as its factorization.

5655821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77550.

The product of its digits is 12000, while the sum is 32.

The square root of 5655821 is about 2378.1970061372. The cubic root of 5655821 is about 178.1688945276.

The spelling of 5655821 in words is "five million, six hundred fifty-five thousand, eight hundred twenty-one".